Change default branch from master to main

[avdev4j]

According to this ticket jhipster/generator-jhipster#11935, we need to change the name of the main branch.

[X] create branch main from master
[X] define main branch as default
[X] protect main
[X] edit existing pull requests

As contributor what should I do?

• Run git fetch to get the main branch back and git push to update your remote fork.
• If I have an opened pull-request?
  Nothing to do, all PR have been edited to target main branch.
• If I have a work in progress?
  If your branch has been created from master please rebase from main, in case commits have been added to it. When you will open the PR GitHub will automatically choose the main branch for you.
• And what about future branches?
  Create new branches from "main" instead of "master". You can delete "master" branch on your fork as it will no been used or updated anymore.
• What about my forked project?
  To update you fork please run this commands:

git fetch
git checkout main
git push --set-upstream origin main

And go to your GitHub repository then Settings -> Branches and change the default branch to main

If you dealing with issues, open a ticket by following our guidelines. We'll try to help you.

cc @danielpetisme @joewhite101

[avdev4j]

Also done for the sample Quarkus project https://github.com/jhipster/jhipster-sample-app-quarkus